From 7ef06b0234706455d4f24375a9389d718e34dbbb Mon Sep 17 00:00:00 2001 From: Rajat Jain Date: Wed, 26 Feb 2020 23:28:02 -0800 Subject: drivers/gfx/generic: Add support for gpio based EPS Add support to control EPS via a PCH gpio Change-Id: I6f570fd43e1649fb23255b0890e01086e34f844a Signed-off-by: Rajat Jain Reviewed-on: https://review.coreboot.org/c/coreboot/+/39154 Tested-by: build bot (Jenkins) Reviewed-by: Mathew King --- src/drivers/gfx/generic/chip.h | 10 ++++++ src/drivers/gfx/generic/generic.c | 76 +++++++++++++++++++++++++++++++++------ 2 files changed, 75 insertions(+), 11 deletions(-) (limited to 'src') diff --git a/src/drivers/gfx/generic/chip.h b/src/drivers/gfx/generic/chip.h index 5e855e3853..714a8aba84 100644 --- a/src/drivers/gfx/generic/chip.h +++ b/src/drivers/gfx/generic/chip.h @@ -16,6 +16,8 @@ #ifndef __DRIVERS_GFX_GENERIC_CHIP_H__ #define __DRIVERS_GFX_GENERIC_CHIP_H__ +#include + /* Config for electronic privacy screen */ struct drivers_gfx_generic_privacy_screen_config { /* Is privacy screen available on this graphics device */ @@ -28,6 +30,12 @@ struct drivers_gfx_generic_privacy_screen_config { const char *enable_function; /* ACPI namespace path to privacy screen disable function */ const char *disable_function; + /* + * GPIO used for controlling the privacy screen. If provided, + * the gpio mechanism takes preference over the functions ptrs + * above, if any (GPIO functions override the function ptrs). + */ + struct acpi_gpio gpio; }; /* Config for an output device as defined in section A.5 of the ACPI spec */ @@ -53,4 +61,6 @@ struct drivers_gfx_generic_config { struct drivers_gfx_generic_device_config device[5]; }; +extern struct device *find_gfx_dev(void); + #endif /* __DRIVERS_GFX_GENERIC_CHIP_H__ */ diff --git a/src/drivers/gfx/generic/generic.c b/src/drivers/gfx/generic/generic.c index 8488040d30..0b3fccafde 100644 --- a/src/drivers/gfx/generic/generic.c +++ b/src/drivers/gfx/generic/generic.c @@ -24,6 +24,11 @@ #define ACPI_DSM_PRIVACY_SCREEN_UUID "C7033113-8720-4CEB-9090-9D52B3E52D73" +#define ACPI_METHOD_EPS_PRESENT "EPSP" +#define ACPI_METHOD_EPS_STATE "EPSS" +#define ACPI_METHOD_EPS_ENABLE "EPSE" +#define ACPI_METHOD_EPS_DISABLE "EPSD" + static void privacy_screen_detect_cb(void *arg) { struct drivers_gfx_generic_privacy_screen_config *config = arg; @@ -62,6 +67,52 @@ static void (*privacy_screen_callbacks[])(void *) = { privacy_screen_disable_cb, }; +static void privacy_gpio_acpigen(struct acpi_gpio *gpio) +{ + /* EPS Present */ + acpigen_write_method(ACPI_METHOD_EPS_PRESENT, 0); + acpigen_write_return_byte(1); + acpigen_pop_len(); + + /* EPS State */ + acpigen_write_method(ACPI_METHOD_EPS_STATE, 0); + acpigen_get_rx_gpio(gpio); + acpigen_emit_byte(RETURN_OP); + acpigen_emit_byte(LOCAL0_OP); + acpigen_pop_len(); + + /* EPS Enable */ + acpigen_write_method(ACPI_METHOD_EPS_ENABLE, 0); + acpigen_enable_tx_gpio(gpio); + acpigen_pop_len(); + + /* EPS Disable */ + acpigen_write_method(ACPI_METHOD_EPS_DISABLE, 0); + acpigen_disable_tx_gpio(gpio); + acpigen_pop_len(); +} + +static void gfx_fill_privacy_screen_dsm( + struct drivers_gfx_generic_privacy_screen_config *privacy) +{ + if (!privacy->enabled) + return; + + /* Populate ACPI methods, if EPS controlled via gpio */ + if (privacy->gpio.pin_count == 1) { + privacy_gpio_acpigen(&privacy->gpio); + privacy->detect_function = ACPI_METHOD_EPS_PRESENT; + privacy->status_function = ACPI_METHOD_EPS_STATE; + privacy->enable_function = ACPI_METHOD_EPS_ENABLE; + privacy->disable_function = ACPI_METHOD_EPS_DISABLE; + } + + acpigen_write_dsm(ACPI_DSM_PRIVACY_SCREEN_UUID, + privacy_screen_callbacks, + ARRAY_SIZE(privacy_screen_callbacks), + privacy); +} + static void gfx_fill_ssdt_generator(struct device *dev) { size_t i; @@ -69,7 +120,7 @@ static void gfx_fill_ssdt_generator(struct device *dev) const char *scope = acpi_device_scope(dev); - if (!scope) + if (!scope || !dev->enabled) return; acpigen_write_scope(scope); @@ -85,17 +136,9 @@ static void gfx_fill_ssdt_generator(struct device *dev) for (i = 0; i < config->device_count; i++) { acpigen_write_device(config->device[i].name); - acpigen_write_name_integer("_ADR", config->device[i].addr); acpigen_write_name_integer("_STA", 0xF); - - if (config->device[i].privacy.enabled) { - acpigen_write_dsm(ACPI_DSM_PRIVACY_SCREEN_UUID, - privacy_screen_callbacks, - ARRAY_SIZE(privacy_screen_callbacks), - &config->device[i].privacy); - } - + gfx_fill_privacy_screen_dsm(&config->device[i].privacy); acpigen_pop_len(); /* Device */ } acpigen_pop_len(); /* Scope */ @@ -117,7 +160,7 @@ static void gfx_enable(struct device *dev) { struct drivers_gfx_generic_config *config = dev->chip_info; - if (!config) + if (!config || !dev->enabled) return; dev->ops = &gfx_ops; @@ -127,3 +170,14 @@ struct chip_operations drivers_gfx_generic_ops = { CHIP_NAME("Generic Graphics Device") .enable_dev = gfx_enable }; + +struct device *find_gfx_dev(void) +{ + struct device *dev; + + for (dev = all_devices; dev; dev = dev->next) { + if (dev->chip_ops && dev->chip_ops == &drivers_gfx_generic_ops) + return dev; + } + return NULL; +} -- cgit v1.2.3